In a typical wireless communication network, wireless devices, also known as mobile stations and/or user equipments (UEs), communicate via a Radio Access Network (RAN) to one or more core networks. The RAN covers a geographical area which is divided into cell areas, with each cell area being served by a base station, e.g., a radio base station (RBS), which in some networks may also be called, for example, a “NodeB” or “eNodeB” (eNB). A cell is a geographical area where radio coverage is provided by the radio base station at a base station site or an antenna site in case the antenna and the radio base station are not collocated. Each cell is identified by an identity within the local radio area, which is broadcast in the cell. Another identity identifying the cell uniquely in the whole wireless communication network is also broadcasted in the cell. One base station may have one or more cells. The base stations communicate over the air interface operating on radio frequencies with the wireless devices within range of the base stations.
A Universal Mobile Telecommunications System (UMTS) is a third generation mobile communication system, which evolved from the second generation (2G) Global System for Mobile Communications (GSM). The UMTS terrestrial radio access network (UTRAN) is essentially a RAN using wideband code division multiple access (WCDMA) and/or High Speed Packet Access (HSPA) for wireless devices. In a forum known as the Third Generation Partnership Project (3GPP), telecommunications suppliers propose and agree upon standards for third generation networks and UTRAN specifically, and investigate enhanced data rate and radio capacity. In some versions of the RAN as e.g. in UMTS, several base stations may be connected, e.g., by landlines or microwave, to a controller node, such as a radio network controller (RNC) or a base station controller (BSC), which supervises and coordinates various activities of the plural base stations connected thereto. The RNCs are typically connected to one or more core networks.
Specifications for the Evolved Packet System (EPS) have been completed within the 3rd Generation Partnership Project (3GPP) and this work continues in the coming 3GPP releases. The EPS comprises the Evolved Universal Terrestrial Radio Access Network (E-UTRAN), also known as the Long Term Evolution (LTE) radio access, and the Evolved Packet Core (EPC), also known as System Architecture Evolution (SAE) core network. E-UTRAN/LTE is a variant of a 3GPP radio access technology wherein the radio base stations are directly connected to the EPC core network rather than to RNCs. In general, in E-UTRAN/LTE the functions of a RNC are distributed between the radio base stations, e.g. eNodeBs (eNB) in LTE, and the core network. As such, the RAN of an EPS has an essentially “flat” architecture comprising radio base stations without reporting to RNCs.
DRX
Discontinuous reception (DRX) reduces battery consumption in the wireless device by limiting the time when receptions need to be monitored. The wireless device can only be scheduled in DL when the wireless device monitors the Physical Downlink Control Channel (PDCCH). This implies that the wireless device can only be scheduled during a fraction of the time, during very specific periods of time when the wireless device is wake, called wake periods defined by an On_Duration_Timer, as shown in FIG. 1. Also an inactivity timer is used before going back to dose/inactivity state after receiving data in a wake period. The short wake periods, or actually the inactivity, sleep, periods of Long_DRX_cycles, reduce the amount of time the wireless device monitors the PDCCH reducing the battery consumption of the wireless device.
It is advantageous to spread the wake periods over time of the wireless devices in order to spread a load, e.g. served wireless devices, due to scheduling in time. This means that the radio access network node attempts to configure the DRX for wireless devices so that different wireless devices do not have simultaneous wake time or wake periods.
However, the performance of the wireless communication network may be reduced when being in DRX mode delaying or failing communication.